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From: Martin Dowie <martin.dowie@btopenworld.com>
Newsgroups: comp.lang.ada
Subject: Re: Various Language Architecture Questions
Date: Sun, 25 Sep 2005 07:24:04 +0000 (UTC)
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Date: 2005-09-25T07:24:04+00:00
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jimmaureenrogers@worldnet.att.net wrote:
> Typecasting is not a way of life for Ada. It is somewhat unusual.
> Ada access types (similar to references in Java) cannot be cast
> from one type to another. Ada uses Unchecked_Conversion for that
> purpose.

You would have to ensure that the underlying representation of each 
access type was the same - Ada does not require that all access types be 
a simple address. Alternatively, you could use 
System.Address_To_Access_Conversions.

But the main point is that in Ada you have to be explicit and it is easy 
to spot these 'dangerous' behaviors.


> You cannot coerce a real number type to or from an integer number
> type.

Are you sure about that Jim? :-)

declare
    I : Integer := 10;
    F : Float   := 1.0;
begin
    F := Float (I);
    I := Integer (F);
end;

Or did you mean something else by 'coerce'?

Cheers

-- Martin